(CNN) -- Susan Boyle's dreams continue to come true. The singing sensation who emerged from obscurity on "Britain's Got Talent" is topping the charts, selling the most albums of any artist in a single week this year with the largest ever sales debut for a female artist.

Boyle's "I Dreamed a Dream" album is on top of the Billboard 200 albums chart with 701,000 copies sold in its first week, according to Nielsen SoundScan.

"This is a big deal considering some of the superstar acts that came out this year that couldn't get to that number, said Billboard's director of charts Silvio Pietroluongo. The year's previous high-water sales mark came when Eminem's "Relapse" sold 608,000 in its opening week.

Boyle, a 48-year-old churchgoing celebrity who lives in a modest government-owned home in Scotland with her pet cat, captured the world's attention and hearts eight months ago when she performed on the British talent competition.

Now Boyle is competing against two "American Idols" for sales this holiday season. Idol runner-up Adam Lambert's debut "For Your Entertainment" is at No. 3 on the Billboard 200, and "Idol" champ Kris Allen is at No. 11.

When it comes to album sales, Boyle is even fiercer than Rihanna, whose fourth album, "Rated R," is in the No. 4 slot on the charts with 181,000 albums sold during the first week.

Boyle's large album sales reflect larger changes happening in the music industry as younger audiences tend to buy single-song downloads, while more mature audiences, who make up Boyle's fan base, still purchase entire albums.

"Hit-driven artists tend to do well on the download side but aren't moving as many albums as they once did," Pietroluongo said. "If you have an artist who resonates with an older audience, you have an artist who can sell more albums."